Photocatalysts can be used to improve our living environment and have been gradually accepted by the consumer public. Under visible light or ultraviolet irradiation, active species is produced on the surface of a photocatalyst particle which can oxidize or reduce the pollutants. Photocatalysts have been used extensively for pollutant removal, air cleaning, water purification, odor removal, sterilization, anti-dust and anti-fog purposes.
Nano-size photocatalysts in the form of particles cannot be used directly. The nanoparticles instead must be immobilized on the surface of a certain substrate, e.g. ceramic, glass, wall, metal or some plastic materials.
Currently the methods for immobilizing photocatalyst on the substrate surface include heating a photocatalyst precursor at high-temperature or using silicon dioxide or resin as adhesive agent. The former method involves high temperatures and consumes energy, thereby limiting the uses of the substrate and reducing the adsorption ability thereof; the latter results in reduced activity of nano-sized photocatalyst due to the presence of an adhesive agent, thereby reducing the photocatalytic degradation efficiency.
Therefore, a novel photocatalyst is desired.